I would change from stepover applied on plane to stepover applied on part, which will improve the tool path and there will be no need to change the tolerance.
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I'm not sure I would want the same cut pattern over the entire cut area.
Have you looked at steep and non-steep settings? The system will use zlevel in the steep areas.
You can see this used in the High Speed Machining tutorial, found in Help > Manufacturing Tutorials.
If the part gets complicated, take a look at cut region management.